Uranium Systems Project

Project description

This project concluded on 30 June 2011.

The Onshore Energy Security Program delivered a wide range of geoscientific datasets which underpin an improved knowledge of Australia's onshore energy resources, including uranium, petroleum, geothermal and thorium. This was achieved via a series of integrated national and regional projects targeted where the maximum impact can be achieved. The Uranium Systems Project was one of the national projects within the Onshore Energy Security Program.

The primary purpose of the Uranium Systems Project was to provide advice to the Australian Government on Australia's uranium resource potential as well as deliver new pre-competitive datasets and concepts to the minerals industry which promote new search areas and reduce risk in the discovery of Australia's uranium resources.

As with other projects under the Onshore Energy Security Program, the Uranium Systems Project worked collaboratively with the State and the Northern Territory geological surveys under the auspices of the National Geoscience Agreement. Collaborative arrangements with universities, industry and other Australian Government agencies, including the CSIRO, were also developed.

Project objectives

• To develop a new understanding of processes which control where and how uranium mineral systems develop
• To map the distribution of known uranium enrichments and related rocks in Australia
• To assess potential for undiscovered uranium deposits at regional to national scales.

Project methodology

The project applied a holistic approach to its investigations of uranium mineral systems. This involved taking a multi-scale view from deposit, to district and crustal scales of the geological processes and spatial controls on uranium mineralisation. An understanding of the key geological factors necessary in the formation of major uranium deposits enabled more rigorous predictions of the potential of greenfield and brownfield terranes for uranium mineralisation. This was particularly important in Australia where uranium-prospective rock units may be concealed beneath extensive regolith or younger sedimentary rocks. The systems approach employed in this project is described in a report on Uranium Mineral Systems which examines the key processes controlling where and how uranium mineralisation occurs in Australia and elsewhere.

The Uranium Systems Project focussed on documenting the spatial distribution of known uranium-rich rocks and uranium occurrences in Australia. This involved compiling of lithogeochemical data and integrating that information with Onshore Energy Secturity Program datasets such as radiometric data re-levelled using results from the Australia-wide geophysical survey (AWAGS2), the National Geochemical Survey, and the 1:1 million geological map of Australia. Aspects of the compilation were also done in collaboration with the Geothermal Energy Project. Results were delivered as a series of digital map products. A series of maps illustrating the large spatial extent of uranium-rich igneous rocks in Australia was produced as part of this project - Uranium content of igneous rocks of Australia 1:5 million maps - Explanatory notes and discussion.

The data compilation and synthesis was complemented by studies aimed at better understanding the processes of uranium transport through the landscape, its deposition and spatial controls on mineralisation. These included petrological and geochronological studies of selected uranium mineralised systems in Australia along with numerical modelling of uranium mineralising processes. The first of these was a study of the Uranium ore-forming systems of the Lake Frome region, South Australia: Regional spatial controls and exploration criteria which applied a 'mineral systems' approach to identify and map the principal geological controls on the location of known uranium mineralisation in this region.

The Uranium Systems Project focussed progressively on regional prospectivity analysis of uranium as new data were acquired in regional project areas. The data included deep and shallow crustal seismic, airborne electromagnetics and geological and geochronological data. Such data enabled 3D models of crustal and basin architecture to be built, which is fundamental to assessments of the potential for uranium mineralisation in each region. The assessments were delivered as a series of map-based 2D and 3D products, highlighting geological elements considered critical in formation of major uranium deposits. An example of a 2D mineral potential maps is available in a report titled An assessment of the uranium and geothermal potential of north Queensland.

Project outcomes

• Increased exploration for known and unrecognised styles of uranium deposits in Australia
• Lower risk for the uranium exploration industry in area selection
• Improved basis for estimation of Australia's uranium resource potential, thereby providing better advice to government
• Industry exploration strategies influenced by increasing the search area for undiscovered uranium resources.

Project outputs

2007-10

• Reports on re-assessments of genetic models of Australian uranium systems and their lithospheric to regional-scale settings
• Maps and Report of the uranium content of igneous and non-igneous rocks of Australia
• Report on the potential for magmatic-related uranium in Australia
• Updated uranium occurrences database (MINLOC)
• Assessments of potential for basin-related uranium mineral systems in selected regions, including sandstone-hosted uranium in the Lake Frome Region of South Australia and in the Eromanga basin.